1. Technical Field
The present invention relates to a method and an apparatus for measuring hematocrit of blood.
2. Description of the Related Art
Hematocrit (HCT) refers to a volume percent of red blood cells in blood, and more particularly, to a relative volume of red blood cells to a volume of blood. In the case of using the hematocrit, since it is possible to know a volume ratio between blood cell components and blood plasma components, information associated with an oxygen amount in blood such as information on anemia may be obtained.
According to the related art, hematocrit of blood is measured using various methods. As a relative simple measuring method, there is a centrifugation method. In the case in which injecting a blood sample in a glass capillary tube and rapidly rotating the glass capillary tube at a high speed, a red blood component in the blood is separated from plasma to form a layer. In this case, a height of the red blood cell layer with respect to the entire height of the blood sample in the capillary tube is measured, thereby obtaining hematocrit. However, in this method, a relatively long time is consumed to measure the hematocrit, and it is impossible to perform hematocrit measurement on flowing blood in real-time.
As another method, the hematocrit may be measured using a Coulter counter. The Coulter counter is a device for measuring a change in electric impedance shown when particles passes through a fine pore, and an average volume percent and the number of individual red cells may be measured using the Coulter counter. However, the Coulter counter is expensive and has a large volume, and it is difficult to carry the Coulter counter.
In the case of electrically measuring hematocrit of flowing blood using the Coulter counter, impedance of blood is changed according to a state of plasma and a change in flow rate, which causes a measuring error of hematocrit. Therefore, a method for measuring hematocrit capable of considering a flow rate as well as a change in a plasma state has been required.